Though Preckwinkle says she isn't running, observers note a mayoral campaign would not be so different from that of Harold Washington. In 1983 Washington had just been re-elected to Congress, yet made a quick turnaround and beat the political odds to become Chicago's first black mayor.

Preckwinkle, if elected, would be the city's first black female mayor.

Losing after one term would be a twist for Emanuel, who took office in 2011, fresh off a cabinet position as Obama's chief of staff. It was Preckwinkle who once mentored Obama in his early days in Chicago.

Preckwinkle supported Obama's run for state Senate in 1996 and his unsuccessful bid for Congress in 2000. She took credit for Obama joining the church of the controversial Rev. Jeremiah Wright, Breitbart reports.

She has since soured on Obama, though, Breitbart notes. She was an Obama delegate in 2008, though she was already expressing doubts about him then.

Among those interested in seeing a Preckwinkle run is leftist radical Bill Ayers.

"She could be a formidable opponent," Ayers told Chicago magazine in December. "But the problem is she doesn’t have anything like the money [Emanuel] has and she screwed herself [by being too close to] the Democratic machine."